Perhaps you should try some spelling variations:
sach hoi » sach doi, sach moi, cach thoi
van hanh » van thanh, ban hanh, van anh
sach dao » lanh dao
sach tao » sach bao, sach tai, sach tham
hanh va » hang va, hanh vi
xuc van » duc van, luc van, vuc van
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
bac hoi » bac ho, bac hoc, bach hoa
ve cam » ve cham, ve cac, va cam
va cua » va chua, via cua, ca cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: su ((sach tao) or (sach dao)) nano ((bac hoi) OR (sach hoi)). hieu ve cam xuc van hanh va cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: su ((sach tao) OR (sach dao)) nano ((bac hoi) OR (sach hoi)). hieu ve cam xuc van hanh va cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "su ((sach tao) or (sach dao)) nano ((bac hoi) OR (sach hoi)). hieu ve cam xuc van hanh va cua tre".
• Adding a wildcard symbol may retrieve word variants: su ((sach tao) or (sach dao)) nano ((bac hoi) OR (sach hoi)). hieu ve cam xuc van hanh va cua tre*.